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A novel near-infrared “turn-on” fluorescent probe for selective detection of Fe3+ and its application in vitro imaging
摘要： A novel near-infrared fluorescent probe RHCC was devised and synthesized. It exhibits high specificity to Fe3+ compared to other metals in aqueous solutions. The detection limit of RHCC was 1.2 × 10-7 M and the complexation stability constant was 5.807 × 104 M-1. The binding ratio of RHCC and Fe3+ was 1:1 which was measured through MS, FTIR and Job’s plot. The energy gap between HOMO and LUMO of RHCC was 3.22 eV, while RHCC-Fe3+ complex was 0.95 eV. This result means the binding of probe RHCC and Fe3+ lowers the RHCC-Fe3+ complex’s energy gap and makes it more stable. What’s more, in living cells and zebrafishes studies, probe RHCC was no significant cytotoxic effect, indicating it could monitor Fe3+ in biological system.
关键词： near-infrared probe,vitro imaging,“turn-on”,high specificity
更新于2025-09-09 09:28:46
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Ultrathin tungsten bronze nanowires with efficient photo-to-thermal conversion behavior
摘要： In this work, we describe a simple one-step solvothermal method to synthesize ultrathin quaternary tungsten bronze nanowires (QTBNWs). In addition, a series of alkali metal-doped QTBNWs can be prepared by simply changing the type of starting alkali carbonate and tungstate. The as-synthesized QTBNWs exhibits strong near-infrared (NIR) rays absorption, high visible light transmission and excellent photo-to-thermal conversion behavior, which are superior to those of tungsten bronze nanorods and ternary TBNWs. And its excellent photothermal performance should be attributed to great localized surface plasmon resonances (SPR).
关键词： solvothermal method,photo-to-thermal conversion,near-infrared absorption,ultrathin tungsten bronze nanowires,surface plasmon resonances
更新于2025-09-09 09:28:46
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EXPRESS: Bulk Protein and Oil Prediction in Soybean Using Transmission Raman Spectroscopy: A Comparison of Approaches to Optimize Accuracy
摘要： Rapid measurements of protein and oil content are important for a variety of uses, from sorting of soybeans at the point of harvest to feedback during soybean meal production. In this study, our goal is to develop a simple protocol to permit rapid and robust quantitative prediction of soybean constituents using transmission Raman spectroscopy (TRS). To develop this approach, we systematically varied the various elements of the measurement process to provide a diverse test bed. First, we utilized an in-house-built benchtop TRS instrument such that suitable optical configurations could be rapidly deployed and analyzed for experimental data collection for individual soybean grains. Second, we also utilized three different soybean varieties with relatively low (33.97%), medium (36.98%), and high protein (41.23%) contents to test the development process. Third, samples from each variety were prepared using whole bean and three different sample treatments (i.e., ground bean, whole meal, and ground meal). In each case, we modeled the data obtained using partial least squares (PLS) regression and assessed spectral metric-based multiple linear regression (metric-MLR) approaches to build robust prediction models. The metric-MLR models showed lower root mean square errors (RMSEPs), and hence better prediction, compared to corresponding classical PLS regression models for both bulk protein and oil for all treatment types. Comparing different sample preparation approaches, a lower RMSEPs was observed for whole meal treatment and thus the metric-MLR modeling with ground meal treatment was considered to be optimal protocol for bulk protein and oil prediction in soybean, with RMSEP values of 1.15±0.04 (R2= 0.87) and 0.80±0.02 (R2= 0.87) for bulk protein and oil, respectively. These predictions were nearly two- to three-fold better (i.e., lower RMSEPs) than the corresponding NIR spectroscopy measurements (i.e., secondary gold standards in grain industry). For content prediction in whole soybean, incorporating physical attributes of individual grains in metric-MLR approach show up to 22% improvement in bulk protein and a relatively mild (up to ~ 5%) improvement in bulk oil prediction. The unique combination of metric-MLR modeling approach (which is rare in the field of grain analysis) and sample treatments resulted in improved prediction models, and using the physical attributes of individual grains is suggested as a novel measure for improving accuracy in prediction.
关键词： near-infrared spectroscopy,Soybean,NIR spectroscopy,MLR,transmission Raman spectroscopy,multiple liner regression,PLS regression
更新于2025-09-09 09:28:46
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Triphenylethylene- and Tetraphenylethylene-Functionalized 1,3-Bis(pyrrol-2-yl)squaraine Dyes: Synthesis, Aggregation-Caused Quenching to Aggregation-Induced Emission, and Thiol Detection
摘要： Three novel pairs of 1,3-bis(pyrrol-2-yl)squaraine dyes, N-alkylated SQ1a?1b, and N-phenylated SQ2a?2b in which triphenylethylene moieties functionalized at 5-position of pyrrole, as well as SQ3a?3b with tetraphenylethylene (TPE) moieties attached at N-position of pyrrole, were synthesized. All six dyes were found not to exhibit aggregation-induced emission (AIE) properties. Spectrophotometric studies showed that N-TPE-functionalized SQ3a?3b exhibited much larger molar extinction coefficients (ε: 1.36?2.14 × 105 M?1 cm?1) than 5,5′-triphenylethylene-functionalized SQ1a?2b (ε: 2.17?8.22 × 104 M?1 cm?1). Surprisingly, SQ2b showed a remarkable red-shifted maximum absorption (λmax: 723 vs 631?652 nm) compared to that of other squaraine dyes. All six squaraine dyes selectively responded to the addition of thiol-containing biomolecules, such as cysteine and gluthatione, with the disappearance of λmax in the near-infrared region in their respective absorption spectra. Interestingly, the thiolated species of SQ3a?3b were AIE active, with the characteristic AIE emission of TPE at λmax = 484?490 nm upon addition of water. Further thiol sensing on solid supports was examined, indicating the potential applications of TPE-functionalized squaraine dyes as bioprobes for the detection of important thiol-containing biomolecules, with a clear change from aggregation-caused quenching to AIE.
关键词： bioprobes,aggregation-induced emission,near-infrared,thiol detection,squaraine dyes
更新于2025-09-09 09:28:46
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Calibration modelling for non-destructive estimation of external and internal quality parameters of ‘Marsh’ grapefruit using Vis/NIR spectroscopy
摘要： Consumer preference for fruit without disorder influences purchase of fruit at both local and international markets. Recent trends in horticulture show that consumer preference is influenced by assurance that external appearance is linked with rewarding internal sensory quality. Therefore, the need for non-destructive evaluation of external and internal quality parameters is important. This study was conducted to develop and test calibration models for integrated prediction of external and internal quality of 'Marsh' grapefruit. Visible to near infrared (Vis/NIR) spectroscopy (Vis/NIRS) was used to acquire spectral information from 522 intact fruit. Reference quality parameters such as colour indices (luminosity (L*), greenness (a*) and yellowness (b*)), rind dry matter (DM), rind total phenolics concentration, BrimA, carbohydrates, sweetness index (SI) and total sweetness index (TSI) were obtained using conventional methods. Principal component analysis was applied to analyse spectral data to identify outliers. Savitzky-Golay second derivative with second order polynomial was employed as pre-processing method to correct light scattering properties of the spectra. The spectra were subjected to a test set validation by categorising the spectra into calibration (60%) and validation (40%) sets. Partial least square regression was used as chemometric tool to develop models for predicting each parameter. The model validation results showed that external and internal quality parameters of grapefruit could be predicted with satisfactory accuracy with R2 value of 0.99 for rind quality parameters (L*, a*, b*, DM) and 0.77, 0.99, 0.99 for BrimA, SI and TSI, respectively. The residual predictive deviation (RPD) results for L*, a*, b*, DM, BrimA, SI and TSI were 64.1, 61.4, 123.4, 12.9, 1.4, 9.0 and 13.9, respectively. Vis/NIR calibration and validation results demonstrated that quality parameters of 'Marsh' grapefruit could be predicted using Vis/NIRS.
关键词： citrus fruit,multivariate data analysis,rind,chemometrics,near infrared spectroscopy,'Marsh' grapefruit
更新于2025-09-09 09:28:46
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Determination of Nitrogen Concentration in Fresh Pear Leaves by Visible/Near-Infrared Reflectance Spectroscopy
摘要： A rapid and reliable method is required to determine the N status of pear (Pyrus communis L.) leaves during the growing season for timely fertilization to improve the yields and fruit quality. In the present study, we evaluated visible and near-infrared reflectance (Vis/NIR) spectra of fresh pear leaves using partial least squares (PLS) regression to determine the N concentration of fresh pear leaves. In addition, we studied the performance of modified spectra generated using different preprocessing techniques. A total of 450 leaf samples were collected from 6-yr-old pear trees of two cultivars, and randomly separated into two subsets (calibration subset [294 samples] and validation subset [180 samples]) after excluding outliers by using principle component analysis. Results showed that the model built using full spectra performed better than that developed using characteristic wavelength segments. In addition, we found that original spectral proved to provide better accuracy than derivative spectra. Among the studied preprocessing techniques, moving average smoothing (MAS) technique improved accuracy the most. Overall results suggested that PLS regression with preprocessing of full spectra using MAS is optimal method for modeling N concentration of fresh pear leaves which yielded 0.961 and 0.953 coefficient of determination (R2) for calibration and cross-validation, respectively. The validation of this method resulted high R2 value (0.847) and low mean relative error (4.48%). In conclusion, this model could provide a rapid and more reliable method to determine the total N concentration in fresh pear leaves and could be useful for fertilization management in pear orchards.
关键词： partial least squares regression,preprocessing techniques,pear leaves,Nitrogen concentration,visible/near-infrared reflectance spectroscopy
更新于2025-09-09 09:28:46
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Near-infrared spectra quantitative analysis for flue gas of thermal power plant based on wavelength selection
摘要： This paper proposed a near-infrared (NIR) spectra quantitative analysis method for flue gas of thermal power plant based on wavelength selection. For the proposed method, the self-adaptive accelerated particle swarm optimization is presented for determining the most representative wavelengths of NIR spectral signals and is combined with partial least square for predicting the various contents of the real flue gas dataset. The proposed method chooses the current own optimal or the current global optimal as the reference state randomly and accelerated updates of the flight velocity by the reference state, then the particle state is updated based on the new velocity self-adaptively. The experimental results of a real flue gas dataset verified that the proposed method has higher predictive ability and could overcome the premature convergence.
关键词： near-infrared spectrum,wavelength selection,fuel gas,Thermal power plant,self-adaptive accelerated discrete particle swarm optimization
更新于2025-09-09 09:28:46
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Targeted near infrared hyperthermia combined with immune stimulation for optimized therapeutic efficacy in thyroid cancer treatment
摘要： Treatment of thyroid cancer has incurred much focus because of its high prevalency. As a new strategy treating thyroid cancer, hyperthermia takes several advantages compared with surgery or chemotherapy, including minimal invasion, low systematic toxicity and the ability to enhance the immunogenicity of cancer cells with the expression Hsp70 which serves as Toll-like receptors-4 (TLR-4 agonist). However, Hsp70 as a molecular chaperone can protect cells from heat induced apoptosis and therefore compromise the tumor killing effect of hyperthermia. In this study, to solve this problem, a combined hyperthermia therapy was employed to treat thyroid cancer. We prepared a probe with the tumor targeting agent AG to monitor thyroid tumor issue and generate heat to kill tumor cells in vivo. At the same time Quercetin (inhibitor of HSP70) and lipopolysaccharide (LPS) (agonist of TLR-4) were used for the combined hyperthermia therapy. The results showed that compared with free IR820, AG modification facilitated much enhanced cellular uptake and greatly pronounced tumor targeting ability. The combined therapy exhibited the most remarkable tumor inhibition compared with the single treatments both in vitro and in vivo. These findings verified that the new therapeutic combination could significantly improve the effect of hyperthermia and shed light on a novel clinical strategy in thyroid cancer treatment.
关键词： IR820,amino-glucose,near infrared hyperthermia,tumor targeting,heat shock protein 70
更新于2025-09-09 09:28:46
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Early Detection of Alzheimer’s Disease Using Non-invasive Near-Infrared Spectroscopy
摘要： Mild cognitive impairment (MCI) is a cognitive disorder characterized by memory impairment, wherein patients have an increased likelihood of developing Alzheimer’s disease (AD). The classification of MCI and different AD stages is therefore fundamental for understanding and treating the disease. This study aimed to comprehensively investigate the hemodynamic response patterns among various subject groups. Functional near-infrared spectroscopy (fNIRS) was employed to measure signals from the frontal and bilateral parietal cortices of healthy controls (n = 8), patients with MCI (n = 9), mild (n = 6), and moderate/severe AD (n = 7) during a digit verbal span task (DVST). The concentration changes of oxygenated hemoglobin (HbO) in various subject groups were thoroughly explored and tested. Result revealed that abnormal patterns of hemodynamic response were observed across all subject groups. Greater and steeper reductions in HbO concentration were consistently observed across all regions of interest (ROIs) as disease severity developed from MCI to moderate/severe AD. Furthermore, all the fNIRS-derived indexes were found to be significantly and positively correlated to the clinical scores in all ROIs (R ≥ 0.4, P < 0.05). These findings demonstrate the feasibility of utilizing fNIRS for the early detection of AD, suggesting that fNIRS-based approaches hold great promise for exploring the mechanisms underlying the progression of AD.
关键词： oxygenated hemoglobin,functional near-infrared spectroscopy,Alzheimer’s disease,hemodynamic response,mild cognitive impairment
更新于2025-09-09 09:28:46
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Potential of Near Infrared Spectroscopy for Classification of Different Delignificant Pre-Treatments on Banana Rachis
摘要： Delignificant pretreatments are fundamental in lignocellulosic materials preprocessing to remove lignin from biomass. Current wet chemical methods are time-consuming, labor-intensive and use hazardous reagents. Near Infrared Spectroscopy (NIRS) provides rapid and non-destructive analysis, and has shown promising results. Spectra collection (8000-4000 cm-1), combined with chemometric analysis based on Cluster Analysis and Principal Component Analysis, has allowed to perform qualitative study of banana rachis, a lignocellulosic residue of agricultural production.
关键词： Near infrared spectroscopy,Cluster analysis,Delignification,Pre-treatments,Banana rachis
更新于2025-09-09 09:28:46